Signor to hacklander



Jan. y27, 1931, c. H. HACKLNDER ELECTROSCOPIG TESTING DEVLCE Filed July 11, 1925 fz'zymfar 'Patented Jan. 27, 1931 UNITED STATS PATENTOFFICE.

CAR-L HnRivrAivNA viriioiznlitnnn, onWnRMniJsKr-acirnir, nrirnnnaivn`- GERMANY, iisg SIGNOR 'ro HACKLNDER & co., oF wnRMriLsKiitcniN, RHrNnLANn, eiaimvraiwv nLEcTRosooPo' 'rnsrriefnnvrcn .Application inea Juiy 1i, i925, seri-.1.1 N0.43,o3e, aan inserita@ muyA is, l1192i;

The objectof the present inventionis to produce an electrosjcope which can be conveniently used for testing in a reliable manner the electric conductivity of textilesand other articles with a view to determine their degree of purity.` Fora device of this kind to be y reliablevin its function, it is essentialtliat the casing which encloses the detecting element should be perfectly non-h'ygroscopic.A To attain this end the casing is according to the present inventionmade of a material which known under the registered trade-mark of Trolit and which is a non-conducting and 4non-hygroscopic cellulose production.

\ sents a sectional view of one formof the apparatus,

Fig. 2, a section on the line 2 2 ofFig. l,

Fig. 3, a sectional .view of a modified form of the apparatus, Y Y

Fig. 4, a section on the line 4 4; of'Fig. 8,

Fig. 5, a sectional view of another modification, p

Fig. 6, a section on the line 6-6 of Fig. 5,

Fig. 7, a section on the line 7-7 of Fig. 5,

Fig. 8, a sectional rdetail view showing the arrangement of the detectorfoil, and

Figs. 9 and l0 are views of modified forms of detecting elements.

' Y In all cases the instrumentis composed of an outer casing a vmade of a material which lis known under the registered trademark of Trolit and which is a non-conducting, nonhygroscopic cellulose production. The casing contains a metal foil 7 or other movable detecting element adapted to be deflected from its normal position under the attraction produced by ay charge ofstatic electricity. To hold suoli charge, the casing is provided with one or more conductors@ arranged with one endinside thecasi'ng in the vicinity of the i detecting elenientand with the other end protruding from the casing forthe reception fof i the.l charge.v The. ends of tliejconductor or conductors'lare preferably 1 enlarged into the outer one the better .to concentrate the charge near the detecten :Apertures covered with windows c of cellon, Celluloid, or the like, l

leather, cellulose or theV like and in such a A. manner that it V.can be rubbed against. said Y paddingfor` producing the charge which is ing constituting the padding. The rod is spheresthe'inner oneof which is smaller-than y.subsequently transferred to Vthe conductor. l

Preferablythe charging elementconsists Vof Y arod rwhich is normallylocated in a felt lined rrecess in the `base of the fcasing,rthe linelectrified by being pulled rapidly out of the casing and4 is then swept over the conductor fortransferring the charge` tothe latter..

with'the charging. rod. Y

velements are preferably mounted in recesses Y ve5l made in a roller gwhich is rotatably heldin the'casingand wliicli'has a nicked head h whereby it can vbe turned` from the outside. The roller may be located in arecess in the casing, as shown in Fig'. 4, in which case the recess` is preferably provided with a metal;

lining n which is in electric ,contact with a metal lining@ for the inner, arched wall ofthe casingp- The conductor Vor conductors@ are insulated fronithe lining ,0. In the' arrange-V ment shown inxFigs. 3 and 4, the roller g is fitted with rfour circumferentially spaced detectingV elements f eitherof whicli.can be Vturned into operative position. When the instrument is not in use, the roller? g is turned into. a position in which all thedetecting ele- 7 5 The rodis preferably connected by means of a. cord of silk or the like to the casing and pre# ventedlin this manner from getting lost.y .'Be- "hind the felt lining in the recess, there is `an elastic cushion r2 of sponge rubber :or the like which :presses 'the lining into good contact ments are covered up and protected Within the recess. A coil spring arranged above the roller g and secured at one end to the casing a is itted at its free end With a catch adapted to enter any of a series of recesses in the roller so as to retain the latter With one o the detecting elements 7" in operative position.

To facilitate the turning of the roller g, it may be mounted as shown in Fig. 5 Where the inner end of the roller is shown drilled to receive a coil spring whereby it is resiliently supported on a ball 7c. The outer end of the roller is formed With a journal whereby it is rotatively held in a nut Z which screws behind the roller into the casing a.

If metal foils are employed as detecting elements, it is convenient to attach them at one end to a stiif piece of paper or cardboard y (Fig. 8) Which can be clamped in the recess of the roller g so as to hold the `l'oilin position in the latter. A more durable detecting element is obtained from a piece of bent Wire which is pivotally held in the roller recess, the ulcrum being adjusted so that the turning moment of' the Wire is equal to that of the metal foil. The detecting element may, as an alternative, consist of a thin but stiff, tapered metal strip which is supported in the roller recess by means of its Widest part so that it Y can be turned about the latter. Figs. 9 and 10 show dierent forms of such detecting elements.

Where tivo conductors are employed in the same instrument, they are preferably arranged at an angle to each other so as to converge towards the detecting element, s shown in Fig. 3.

In order to render the interior of the casing easily accessible, the sides b may be arranged in dovetail grooves, as shown in Fig. 7, so as to be removable from the` casing. They may be held in position by a cross slide d (Fig. 5) which is also held in a dovetail groove.

I claim:

l. 15in electroscope comprising a casing of non-conducting, non-hygroscopic material, a roller supported rota/tively in said casing, a detecting element held in a recess in said roller so that it can be deflected from the latter, and a conductor held in the casing With one end outside and the other inside the casing, the inside end being located in the vicinity of lthe detecting element, the casing being provided with aA lined recess for the reception of a charging rod.

2. The structure claimed in claim l Wherein the roller is mounted in a recess in the casing, and interconnected metal linings for the casing itself and for the roller recess.

3. The structure claimed in claim l, and a spring catch adapted to hold the roller with the detecting element either in or out of operative position.

4f. The structure claimed in claim l Where- CARL HERMANN HACKLNDER. 

